Chickenpox vaccine

The chickenpox vaccine, also known as a varicella vaccine, is a vaccine which specifically gives protection against the virus which causes chickenpox. The vaccine became available to the public in 1984 and it is recommended by the World Health Organization on its list of essential medication. In most groups, it is a safe and effective intervention.

How much protection does the chickenpox vaccine give?

The vaccine is not 100% effective, although if you do get the vaccine and get chickenpox, symptoms will generally be milder than if you did not have the vaccination done. It is 70% to 90% effective at preventing chickenpox.

How long is the chickenpox vaccine effective for?

The duration of efficacy of the vaccination is unknown. There have been cases where the vaccine was effective for over 20 years, which suggests they have developed life-long immunity to the vaccine. However, in certain cases, it has been effective for only around 6 years. Research suggests that children have a better and more long-lasting response to the vaccine as compared to adolescents and adults. Studies are still being conducted to understand how long the vaccination is effective.

How does the chickenpox vaccine work?

The vaccination is what is known as a live vaccine. What this means, is that it contains a small amount of active, but chemically weakened varicella virus. The vaccination stimulates your body’s immune system to produce long-term antibodies which protect against the virus.

How is the chickenpox vaccine given?

The vaccine is given as an injection in the upper arm region, although the injection site can be changed in certain cases. Note that a second injection is often required, typically one or two months after the first injection. This makes the vaccination more effective and long-lasting.

Chickenpox vaccine side effects

Side effects of the varicella vaccine are still not properly understood and there are still studies being conducted. But, this is what we know so far:

Side effects of the chickenpox vaccine are generally mild and include

Soreness at the site of injection (injection site reaction)

Fever

Rash typically found around or near the injection site

Studies show around 5% of children will develop either a fever or a rash after the vaccination is administered.

More severe reactions are extremely uncommon and include

Some patients might experience an allergic reaction (anaphylaxis) due to the vaccine or one or more of its excipients. This is extremely rare.

Pneumonia and meningitis have been reported in certain rare cases.

Is the chickenpox vaccine suitable for me?

The chickenpox vaccine is contraindicated (not suitable) for the following patients:

Women that are pregnant

People who have a gelatin or neomycin allergy

People receiving high doses of steroid therapy

People undergoing chemotherapy and/or radiotherapy

People who have received blood transfusions and/or blood products in the past five months